JP2008078190A - Substrate treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment apparatus which can prevent contamination of a substrate by contriving supplying of air for drying. <P>SOLUTION: A control section 45 makes an electric dumper 35 switch to normal discharge, and after efficient rinsing is completed, it changes over the electric dumper 35 to a gas supply section 23. At the same time, a lifter 15 is elevated, and the gas for drying is fed from the gas supply section 23 to a substrate W exposing over the level of a rinsing liquid, to make the substrate W dried. Thus, gas for drying will not be supplied from the has supply section 23 during processing by a processing liquid-containing chemicals or under the initial state of rinsing; and SiO<SB>2</SB>particles that are produced by the processing liquid-containing chemicals will not be taken in. Thus, contamination of the substrate W can be prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus that performs a predetermined process on a glass substrate (hereinafter simply referred to as a substrate) for a semiconductor wafer or a liquid crystal display device, and in particular, performs a drying process on a substrate while pulling up the substrate from a processing solution. It is related to the technology to do.

  Conventionally, as this type of apparatus, a processing tank for storing a processing liquid, a lifter configured to support a substrate and can be moved up and down over the inside of the processing tank and above the processing tank, and provided near the liquid surface of the processing tank And a nozzle provided with a nozzle for supplying a drying gas in the horizontal direction (see, for example, Patent Document 1).

In the apparatus configured in this way, for example, the lifter is lowered in a treatment tank storing pure water to immerse the substrate in pure water, and then hydrofluoric acid is mixed in the treatment tank for etching. A treatment liquid is generated. Then, after the treatment for a predetermined time, pure water is supplied to replace the treatment liquid containing hydrofluoric acid with pure water. After rinsing with pure water for a predetermined time, the lifter is raised while supplying the drying gas from the nozzle. Thereby, the substrate pulled up from the liquid surface of the processing liquid is dried by the drying gas. Since the dry air supply device takes a long time to generate a drying gas having a high dew point, it is generally operated at all times. Therefore, the drying gas is supplied from the supply unit even when the processing with the etching processing liquid is performed.
JP 11-354488 A

However, the conventional example having such a configuration has the following problems.
That is, when a treatment liquid containing hydrofluoric acid is used as the treatment liquid, the oxide film (SiO ₂ ) of the substrate is etched by a reaction of SiO ₂ + 6HF → H ₂ SiF ₆ + 2H ₂ O, and hydrofluorosilicic acid ( H ₂ SiF ₆ ) is produced. Thereafter, hydrolysis of H ₂ SiF ₆ + 2H ₂ O → SiO ₂ + 6HF occurs, and SiO ₂ particles are generated in the treatment liquid. By the way, the processing liquid overflowing from the processing tank is discharged almost uniformly around the processing tank, but the liquid level of the processing liquid is biased by the drying gas. As a result, since the liquid level of the processing liquid blown by the drying gas is dried, there is a problem that the SiO ₂ particles contained in the processing liquid are wound up by the drying gas and the substrate is contaminated.

  In the above description, a treatment liquid containing hydrofluoric acid is taken as an example. However, even with other treatment liquids, there is a possibility that particles are generated and the substrate is contaminated.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the substrate processing apparatus which can prevent the contamination of a board | substrate by devising supply of the gas for drying.

In order to achieve such an object, the present invention has the following configuration.
That is, according to the first aspect of the present invention, in the substrate processing apparatus for dipping the substrate in the processing liquid and then lifting the substrate from the processing liquid and drying the substrate, the processing tank storing the processing liquid and the processing tank A treatment liquid supply means for supplying a chemical solution and pure water as a treatment liquid, a support means for supporting the substrate and moving up and down in the treatment tank and above the treatment tank, and provided near the liquid surface of the treatment tank A gas supply means for supplying a drying gas from the side of the substrate supported by the support means; a first state in which a drying gas is supplied from the gas supply means; and a drying state from the gas supply means Switching means for switching to a second state in which gas is exhausted without being supplied; and in the second state, the substrate is processed with a chemical solution supplied from the processing liquid supply means to the processing tank; Supplier The substrate is treated with pure water supplied to the treatment tank, and after the substrate has been sufficiently treated with pure water, the switching means switches the second state to the first state, and the support And a control means for supplying a drying gas by the gas supply means to the substrate exposed from the pure water surface by raising the means from the pure water in the treatment tank. is there.

  [Operation / Effect] According to the first aspect of the present invention, the control means causes the substrate to be treated with the chemical solution supplied from the treatment liquid supply means to the treatment tank in the second state, and further the treatment liquid supply means performs the treatment. The substrate is treated with pure water supplied to the tank, and after the substrate is sufficiently processed with pure water, the switching means is switched from the second state to the first state, and the support means is placed in the pure water in the treatment tank. A drying gas is supplied by the gas supply means to the substrate that is raised from the water and exposed from the liquid surface of the pure water. Therefore, the drying gas is not supplied from the gas supply means during the treatment with the treatment liquid containing the chemical liquid or in the initial state of rinsing, and the particles generated by the treatment liquid containing the chemical liquid are not rolled up. Therefore, contamination of the substrate can be prevented.

  Moreover, in this invention, it further comprises the specific resistance meter which measures the specific resistance value of the pure water in the said processing tank, The said control means from said 2nd state according to the output signal from the said specific resistance meter. It is preferable to cause the switching means to switch to the first state. By switching the switching means from the second state to the first state according to the specific resistance value by the specific resistance meter, particles generated by the treatment liquid including the chemical liquid are discharged from the pure water, and the rinsing is sufficiently performed. It can be accurately determined whether or not.

  In the present invention, it is preferable that the control means stops the supply of pure water from the treatment liquid supply means in accordance with an output signal from the resistivity meter (Claim 3), and sandwiches the treatment tank. It is preferable that a gas discharge means for discharging the drying gas is further provided at a position facing the gas supply means (Claim 4).

  In the present invention, it is preferable that the gas supply means and the gas discharge means are made of engineering plastics or fluororesin. Since the treatment liquid stored in the treatment tank is resistant even if the treatment liquid contains hydrofluoric acid, the generation of particles due to corrosion of the gas supply means and the gas discharge means can be prevented.

  According to the substrate processing apparatus of the present invention, the control means causes the substrate to be processed by the chemical solution supplied from the processing liquid supply means to the processing tank in the second state, and is further supplied from the processing liquid supply means to the processing tank. After the substrate is treated with pure water and the substrate is sufficiently treated with pure water, the switching means switches from the second state to the first state, and the support means is raised from the pure water in the treatment tank. A drying gas is supplied to the substrate exposed from the liquid surface of the pure water by the gas supply means. Therefore, the drying gas is not supplied from the gas supply means during the treatment with the treatment liquid containing the chemical liquid or in the initial state of rinsing, and the particles generated by the treatment liquid containing the chemical liquid are not rolled up. Therefore, contamination of the substrate can be prevented.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram illustrating a schematic configuration of a substrate processing apparatus according to an embodiment.

  The substrate processing apparatus according to this embodiment includes a processing tank 1 for storing a processing liquid. The processing tank 1 is configured to store a processing liquid and accommodate a plurality of substrates W in an upright posture. At the bottom of the processing tank 1, two ejection pipes 7 having a long axis along the direction (paper surface direction) in which a plurality of substrates W are aligned are provided for supplying a processing liquid. Yes. One end side of a supply pipe 9 is connected to each ejection pipe 7, and the other end side of the supply pipe 9 is connected to a processing liquid supply source (not shown). The supply pipe 9 supplies chemical liquid such as hydrofluoric acid (HF), pure water, or the like as a processing liquid.

  The processing tank 1 is surrounded by a chamber 11. The chamber 11 includes an upper cover 13 that can be freely opened and closed. The lifter 15 that holds the plurality of substrates W in a standing posture includes a “standby position” that is above the chamber 11, a “processing position” that is inside the processing tank 1, and an inside of the chamber 11 that is above the processing tank 1. It is configured to be movable across the “drying position”.

  The two jet pipes 7 described above correspond to the processing liquid supply means in the present invention, and the lifter 15 corresponds to the support means in the present invention.

  A discharge port 17 is formed at the bottom of the processing tank 1. A QDR valve 19 is attached to the discharge port 17. When the processing liquid in the processing tank 1 is discharged from the QDR valve 19, the processing liquid is once discharged to the bottom of the chamber 11. A drain valve 21 is attached to the bottom of the chamber 11. When the drain valve 21 is opened, the processing liquid discharged into the chamber 11 is discharged to the outside.

  In the chamber 11, a gas supply unit 23 for supplying a drying gas is disposed on the side of the upper edge of the processing tank 1. Further, a gas gas discharge unit 25 for discharging the drying gas is disposed at a position facing the gas supply unit 23 with the processing tank 1 interposed therebetween. The gas / gas supply unit 23 includes an injection port 27 that ejects a drying gas so as to open near the liquid surface of the processing liquid stored in the processing tank 1, and the gas discharge unit 25 stores the drying gas in a chamber. 11 is provided with a discharge port 29 for discharging to the outside of the processing tank 1.

  The gas supply unit 23 described above corresponds to the gas supply unit in the present invention, and the gas discharge unit 25 corresponds to the gas discharge unit in the present invention.

  The gas supply unit 23 is connected to the other end of a supply pipe 33 whose one end is connected to the dry air supply device 31. The dry air supply device 31 supplies air adjusted to a high dew point as a drying gas (dry air). The supply amount is adjusted by an electric damper 35 provided in the supply pipe 33. The electric damper 35 adjusts the supply amount of the drying gas to the gas supply unit 23 (first state), and supplies all the drying gas to the gas supply unit 23 to the general exhaust, 23 is provided with a function of stopping the supply of the drying gas to 23 (second state). The gas supply unit 23, the supply pipe 33, and the gas discharge unit 25 are made of engineering plastics such as polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), tetrafluoroethylene, It is preferably made of a fluororesin such as perfluoroalkyl vinyl ether copolymer (PFA).

  The electric damper 35 described above corresponds to the switching means in the present invention.

  In addition, an electric damper 37 is disposed in the gas discharge unit 25. The electric damper 37 is used to adjust the flow rate of the drying gas discharged from the gas discharge unit 25.

  A specific resistance meter 39 for measuring the specific resistance of pure water stored in the processing tank 1 is disposed at one portion of the side wall of the processing tank 1. After being instructed to start measurement, the specific resistance meter 39 outputs the specific resistance values sequentially measured as an output signal SR.

  The chamber 11 also includes an exhaust pipe 41 for exhausting the internal gas. The exhaust pipe 41 includes a flow rate control valve 43, and the exhaust flow rate from the chamber 11 is adjusted by the flow rate control valve 43.

  The control unit 45 corresponding to the control means of the present invention controls the above-described opening and closing of the upper cover 13, raising and lowering of the lifter 15, opening and closing of the QDR valve 19 and the drainage valve 21, and opening degrees of the electric dampers 35 and 37. Do. In addition, control for switching the drying gas from the general exhaust to the supply pipe 33 (from the second state to the first state) by adjusting the opening of the electric damper 35 according to the output signal from the resistivity meter 39. And so on.

  Next, the operation of the above-described apparatus will be described with reference to FIGS. 2 to 5 are diagrams for explaining the operation.

Here, it is assumed that an oxide film (SiO ₂ ) has already been deposited on the substrate W to be processed. Also, pure water is supplied from the supply pipe 9 to the treatment tank 1, and then etching is performed by injecting hydrofluoric acid (HF). Then, after supplying pure water and rinsing, a drying gas is supplied. The substrate W will be lifted up while being supplied, and the cleaning and lifting / drying of the substrate W will be described as an example. It is assumed that the QDR valve 19 is closed and the drain valve 21 is opened. The electric damper 35 is adjusted so that the drying gas from the dry air supply device 31 is supplied to the general exhaust (second state).

  The control unit 45 supplies pure water as a treatment liquid from the supply pipe 9 to the treatment tank 1. Pure water overflowing the treatment tank 1 is collected at the bottom of the chamber 11. The upper cover 13 is opened, and the lifter 15 holding the substrate W is lowered from the standby position to the processing position. Then, the substrate W is washed with pure water for a predetermined time (FIG. 2).

When the pure water cleaning for a predetermined time is completed, the controller 45 injects hydrofluoric acid (HF) into the pure water to generate a processing solution for etching (FIG. 3). As a result, the oxide film deposited on the surface of the substrate W is etched, and hydrofluorosilicic acid (H ₂ SiF ₆ ) is dissolved in the etching processing liquid stored in the processing tank 1. On the other hand, the remaining hydrofluorosilicic acid is retained as SiO ₂ particles in the treatment liquid by hydrolysis. Most of the hydrofluorosilicic acid is discharged from the treatment tank 1 by supplying pure water and hydrofluoric acid from the ejection pipe 7, but a part of the hydrofluorosilicic acid stays in the treatment tank 1.

  When the control unit 45 finishes the etching process for a predetermined time with the treatment liquid containing hydrofluoric acid, the control unit 45 stops the supply of hydrofluoric acid, and supplies only pure water to the treatment tank 1 through the supply pipe 9. Rinse is performed (FIG. 4). After starting to supply only pure water, the controller 39 monitors the output signal SR from the specific resistance meter 39 and continues to supply pure water until a predetermined specific resistance value is reached.

  When the output signal SR reaches a predetermined value and the specific resistance value of pure water in the processing tank 1 reaches a predetermined value, the control unit 45 stops the supply of pure water and connects the electric damper 35 to the supply pipe 33 side. , The drying gas is supplied from the gas supply unit 23 (first state), the electric damper 37 is adjusted, and the drying gas is exhausted from the gas discharge unit 25 at a predetermined flow rate (FIG. 5). Further, the lifter 15 starts to be raised to a drying position at a predetermined speed, and the QDR valve 19 is opened to begin to rapidly drain pure water in the treatment tank 1.

  Thereby, the drying gas is injected from the injection port 27 of the gas supply unit 23, and the drying gas passes through the plurality of substrates W and is discharged from the gas discharge port 29. Therefore, the plurality of substrates W supported by the lifter 15 are dried by the drying gas. After being raised to the drying position, the upper cover 13 is opened, and the lifter 15 is raised to the standby position to complete the process.

As described above, the control unit 45 switches the electric damper 35 to the general exhaust, and after the rinse is sufficiently performed, the control unit 45 switches the electric damper 35 to the gas supply unit 23 side and raises the lifter 15. The drying gas is supplied from the gas supply unit 23 to the substrate W exposed from the liquid surface of the rinsing liquid, and the substrate W is dried. Therefore, during the treatment with the treatment liquid containing the chemical liquid or in the initial state of rinsing, the drying gas is not supplied from the gas supply unit 23, and the SiO ₂ particles generated by the treatment liquid containing the chemical liquid are the liquid of the treatment liquid. It is not rolled up from the surface. Therefore, contamination of the substrate W can be prevented.

  Further, since the control unit 45 determines the completion point of rinsing based on the output signal SR of the specific resistance meter 39, it can be accurately determined whether the rinsing is sufficiently performed.

<Comparison of effects>
Here, a comparison between the present embodiment apparatus and the conventional apparatus will be described with reference to FIGS. FIG. 6 is a table showing the number of increased particles after and after processing by the apparatus of this embodiment, and FIG. 7 is a table showing the number of increased particles by the conventional apparatus.

  6 and 7, slots 1, 24, 50 indicate locations where the plurality of substrates W supported by the lifter 15 are supported. That is, the slot 1 indicates the substrate W supported by the first slit. As apparent from the comparison between FIG. 6 and FIG. 7, according to the apparatus of this embodiment, it is understood that the increase in the number of particles adhering to the processing is extremely small as compared with the conventional apparatus, and contamination of the substrate W due to the processing can be prevented.

  The present invention is not limited to the above embodiment, and can be modified as follows.

  (1) In the above-described embodiment, the specific resistance meter 39 is provided, the supply of the drying gas is started in accordance with the output signal SR and the lifter 15 is raised, but the approximate time for the specific resistance value to rise to a predetermined value. If the specific resistance meter 39 is known, the specific resistance meter 39 may be omitted, the rinsing may be started, the time may be measured, and the supply of the drying gas may be started when the time has elapsed. This simplifies the configuration and control.

  (2) In the above-described embodiment, the drying gas is switched between the gas supply unit 23 and the general exhaust by the electric damper 35. However, this may be constituted by a three-way valve and a flow control valve.

  (3) In the embodiment described above, the processing tank 1 is constituted by a single tank, but it may be a multiple tank including an inner tank and an outer tank for recovering the processing liquid overflowing from the inner tank.

  (4) In the above-described embodiments, hydrofluoric acid is used as an example of the chemical solution. However, other chemical solutions such as sulfuric acid and hydrogen peroxide, hydrochloric acid, phosphoric acid, and the like are also used. The effect of.

It is a block diagram which shows schematic structure of the substrate processing apparatus which concerns on an Example. It is a figure where it uses for operation | movement description. It is a figure where it uses for operation | movement description. It is a figure where it uses for operation | movement description. It is a figure where it uses for operation | movement description. It is a table | surface which shows the increase number of the particle | grains by a present Example apparatus. It is a table | surface which shows the increase number of the particle | grains by a prior art example apparatus.

Explanation of symbols

W ... Substrate 1 ... Processing tank 7 ... Jet pipe 9 ... Supply pipe 11 ... Chamber 15 ... Lifter 17 ... Discharge port 19 ... QDR valve 23 ... Gas supply part 25 ... Gas discharge part 31 ... Dry air supply device 33 ... Supply pipe 35, 37… Electric damper 39… Resistivity meter 45… Control valve SR… Output signal

Claims (5)

In the substrate processing apparatus for dipping the substrate in the processing liquid and then lifting the substrate from the processing liquid and drying the substrate,
A treatment tank for storing the treatment liquid;
A treatment liquid supply means for supplying a chemical solution and pure water as a treatment liquid to the treatment tank;
A support means for supporting the substrate and capable of moving up and down over the inside of the processing tank and above the processing tank;
A gas supply means for supplying a drying gas from the side of the substrate provided near the liquid surface of the processing tank and supported by the support means;
Switching means for switching between a first state in which a drying gas is supplied from the gas supply means and a second state in which the drying gas is exhausted without being supplied from the gas supply means;
In the second state, the substrate is treated with the chemical solution supplied from the treatment liquid supply means to the treatment tank, and the substrate is further treated with pure water supplied from the treatment liquid supply means to the treatment tank. After the substrate has been sufficiently treated with water, the switching means switches from the second state to the first state, and the support means is raised from the pure water in the treatment tank to obtain a pure water solution. Control means for supplying a drying gas by the gas supply means to the substrate exposed from the surface;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
Further comprising a resistivity meter for measuring a resistivity value of pure water in the treatment tank;
The substrate processing apparatus, wherein the control means causes the switching means to switch from the second state to the first state in accordance with an output signal from the resistivity meter. The substrate processing apparatus according to claim 2,
The substrate processing apparatus characterized in that the control means stops the supply of pure water from the processing liquid supply means in response to an output signal from the resistivity meter. In the substrate processing apparatus of Claim 1 to 3,
A substrate processing apparatus, further comprising gas discharge means for discharging a drying gas at a position facing the gas supply means across the processing tank. The substrate processing apparatus according to claim 4,
The substrate processing apparatus, wherein the gas supply means and the gas discharge means are made of engineering plastics or fluororesin.

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